I'm looking for a window air conditioner that will keep a 250 sq ft room cool

And according to half the country was around 100 degrees yesterday, we all need a GOOD air conditioner!!  Well, my old house that I was renting has about that size living room , it was like a double room, and the doorway was open to the kitchen, which was also huge.  We got an 8000 BTU window a/c and it really cooled the living room, sometimes even made it downright cold, it even cooled off the kitchen nicely, of course we did have the ceiling fan on to help at that though.  So I will suggest any brand name that you like, just make sure you get at least an 8000 BTU or higher!